Cross-Unit Initialization Dependencies

What this C++ initialization-order interview question tests

This is a medium-difficulty C++ question that probes your understanding of static initialization order across translation units—a subtle but critical area in which many candidates stumble. It rewards careful reasoning about when global and static objects are constructed and how their lifetimes interact.

To solve problems like this, you need to track the order in which the compiler and linker construct static-duration objects in different compilation units, understand the rules governing initialization dependencies, and predict the resulting output. Interviewers ask these questions because they reveal whether you can reason about non-local program behaviour and avoid common pitfalls that lead to undefined or surprising results in large codebases.

• Static initialization order fiasco
• Translation unit boundaries and linking
• Constructor and destructor sequencing
• Global object lifetime and visibility